(1) Field of the Invention
The invention relates to a method for managing power, and more particularly, to a method for managing power of a mobile communication device that accesses data through an internet.
(2) Description of the Prior Art
In addition to the basic function of communication, the mobile communication devices have been developed from the second generation voice phone to the third generation video phone, and even include a plurality of functions, such as digital camera, MP3 player, and even global positioning system (GPS). Such functions require more elements, and thus electrical currents are increasing. Compared with the second generation voice phone, power consumption has been nearly doubled. However, consumers hope that the operation time can be longer and that batteries can provide a stable current for a longer time. Therefore, it is the priority for research and development engineers to make the power management excellent to support mobile communication devices of the new generation.
In addition to choosing good rechargeable batteries and to supervising and managing the rechargeable batteries, adjusting, according to use status of the mobile communication device, functions of the elements for reducing the power consumption can make the service lives of the batteries longer. Generally, the mobile communication devices have three power modes, i.e., off mode, on mode, and sleep mode.
When in the off mode, internal elements in the mobile communication device are in the off status. At that time, the communication between the mobile communication device and a base station is cut out. The on mode means that the mobile communication device is in use or in other operations, that the main internal elements, such as central processing unit (CPU) and other peripheral elements, in the mobile communication device consume working voltages, and that only very few elements, such as backlight module, that consumes larger power consumption will be switched off in order to save energy. When the mobile communication device is idle for a certain time, then power status of the mobile communication device will enter the sleep mode. At that time, the CPU enters the sleep status, but the mobile communication device still has the communication with the base station. When the mobile communication device receives calls from the base station, or sensors operation of user, then the mobile communication device will shift from the sleep mode into the on mode.
Please refer to FIG. 1A which shows that the mobile communication device in the prior is in the sleep mode. As shown in FIG. 1A, the mobile communication device 10 includes: a central processing unit 101 and a wireless communication unit 102, wherein the central processing unit (CPU) 101 is connected to the wireless communication unit 102, and the wireless communication unit 102 usually communicates with a base station 11 through radio waves, and registers where the mobile communication device 10 is. When the mobile communication device 10 is idle for a certain time, then the mobile communication device 10 enters the sleep mode. At that time, the voltage that is supplied to the CPU 101 is lowered, and the CPU 101 enters the sleep mode having simplified functions in order to reduce the power consumption, and to extend the service lives of the batteries, moreover, the wireless communication unit 102 still works normally and keeps communicating with the base station 11.
Please refer to FIG. 1B which shows that the mobile communication device in the prior is in the on mode. When the base station 11 transmits a call signal to the mobile communication device 10, then the wireless communication unit 102 will stop the sleep mode of the CPU 101, so that the CPU 101 will return back to the on mode that consumes working voltage, and then the mobile communication device 10 will enter the on mode.
With the fast development of mobile communication technology, user can contact the internet to browse information, and even can receive and send e-mails, especially, the new generation people always focus on receiving the e-mails. When a new e-mail that is going to be sent to the user is sent to a mail server, then system will send a short message service (SMS) to the mobile communication device, and then the user will receive the e-mail through operation of the user himself.
However, when the aforesaid mobile communication device 10 is in the off mode, which means that the communication with outside is stopped, then the user cannot know the real-time information. To businessmen who emphasize the information, it is a pity that they cannot know the real-time information.
On the other hand, in order to increase the convenience of the mobile communication device, the portable mobile communication device should have a function of an automatically accessing data to the internet for the user to browse whenever and wherever.
However, when the mobile communication device 10 is connected to the internet through the TCP/IP, the CPU 101 is required to carry out such a connection. If the CPU 101 is in the sleep mode, then the mobile communication device cannot be connected to the internet and thus, cannot access data. If the CPU 101 is always in the on mode in order to be connected to the internet, then the energy of the battery will be consumed rapidly, and thus duration time of the battery is dramatically shortened.